4. INVENTORIES (Details Narrative) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Cost of contract manufacturing	$ 11,731	$ 10,951	$ 32,972	$ 47,641
Idle Capacity Costs [Member]
Cost of contract manufacturing	$ 1,740	$ 6,392	$ 5,344	$ 11,182

The aggregate cost of goods produced and sold and services rendered during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration